Nitrogen can be liquefied using a Joule-Thomson expansioniprocess. This is done by rapidlyl and adiabatically expandign coldnitrogen gas from high pressure to a low pressure. If nitrogen at135 K and 20 MPa undergoes a Joule-Thomson expansion to 0.4MPa,
a. Estimate the fraction of vapor and liquid present after theexpansion, and the emperature of this mixture using thepressure-enthalpy diagram for nitrogen.
b. Repeat the calculation assuming nitrogen to be an ideal gaswith Cp* = 29.3 J/molK
